Caps, hats and other forms of head covers, are typically made of some kind of fabric selected primarily for its ability to shield the wearer's head from the rays of the sun, from cold weather or from moisture. A very popular kind of cap is referred to by many as a "baseball" cap irrespective of whether it is being used in some kind of sport, for hunting, for work or other application. Such a cap typically comprises a flexible portion which covers the head and an outer relatively stiff panel portion which provides shade for the eyes. The head cover portion is called the crown and the shade portion is referred to as the bill.
A typical method of fabricating a baseball cap of the type referred to is to precut a selected number of panels from a sheet of fabric and seam these together to form the crown to which the bill is attached. For purposes of adjustment to different head sizes, the cap is typically fitted with an adjustable strap at the rear of the cap and a somewhat inverted U-shape opening is left in the crown portion above the location of the strap. In some types of caps of the kind being described, a large portion and sometimes the entire portion of the crown, is formed of a porous net material. In some instances, the fabric composite from which the crown panels are cut comprises an outer cloth layer which may be either natural or synthetic and a thin inner layer which also may be either natural or synthetic and which is bonded to the outer layer to form an inner lining for the cap.
So far as is known, the popular type of cap described has never been fabricated in a form suited to the purpose of shielding the head from radiation such as emitted by television sets, microwave ovens, citizens-band (CB) radios, cordless telephones and the like. Yet, there is increasing concern and numerous studies and research articles indicate there is cause for concern when a person for whatever reason is continuously exposed to certain frequencies. This concern centers to a great concern on potential damage to the brain.
The technology for making surface metallized fabrics suited for use as personal protective clothing is described in U.S. Pat. Nos. 3,164,840; 4,420,757; 4,278,435; 4,439,768; and 4,572,960 the teachings of which are incorporated herein by reference.
A radiation protective garment having a head covering formed of a metallized fabric is described in U.S. Pat. Nos. 3,164,840; 4,338,686; and 4,572,960 and more recently in U.S. Pat. No. 5,073,984, the teachings of which patents are incorporated herein by reference.
The fabrics, referred to above as surface metallized fabrics, are now being produced and sold so far as applicant is aware, primarily for industrial applications as for example, being applied somewhat like wallpaper to shield a room from electric field, electromagnetic field, and other radio frequency interference. One such fabric is sold under the trademark "Flectron" by Monsanto Chemical Company of St. Louis, Mo. So far as is known, no one has heretofore recognized either the possibility or suitability of applying such shielding material to the manufacture of the popular and widely used baseball-type cap so as to make the cap a selective frequency shielding device for the head without impairing the ability of the cap to be a baseball-type cap bead cover.